The present invention is concerned with food for ornamental or aquarium fish. More particularly, it is concerned with a stable foodstuff which can be placed in an aquarium tank for prolonged feeding of ornamental fish over a period of several days.
Owners of ornamental or aquarium fish face the problem of feeding the fish over periods when the owners are on holiday (vacation) or are otherwise away from home for periods of several days.
Feed masses for fish which are stable for a long time in water are known, but they generally suffer from a number of serious disadvantages. These so-called feed blocks or feed stones have an organic content of only 2.2% to 2.7% by weight, of which about only 1% by weight is crude protein. The remainder of the feed block consists of nonutilizable inorganic components, mainly calcium sulfate, which impair aquarium water.
When these feed blocks are used, a considerable increase in the calcium and sulfate ion concentrations occur in the aquarium water, both of which are objectionable with regard to the osmotic effects on ornamental fish. A consequence of prolonged feeding using these feed blocks is the considerable increase in conductivity of the aquarium water with attendant damage to the fish and aquarium plants and adulteration of the aquarium water. Therefore, these feed blocks or feed stones are unsuitable as sources of foodstuffs for aquarium fish.